Cable



Jan. 23, 1934. c. P. BRODHUN CABLE Original Filed May 5, 1927 2Sheets-Sheet l Jan. 23, 1934.

c. P. BRODHUN 1,944,634

CABLE 2 Sheets-Sheet 2 Original Filed May 5, 1927 Patented Jan. 23, 1934Y CABLE Carl P. Brodhun, Wilkes-Barre, Pa.

Application May 5, 1927, Serial No. 189,117 Renewed September 8, 1932 3Claims.

This invention relates in general to cables and more particularly hasreference to insulated electric cables.

The insulation of cables of this character in the 5 past has beenattended With the problem of providing a protective covering for thecable, either as a part of the body or a separate casing that willeiciently resist the deleterious effects of the elements. This problemis encountered primarily in the insulation of submarine and subterraneancables, though it is met to some degree in aerial cables as well.

As a solution of the problem, cables of this type have been encased interra cotta, wood and metal conduits or have been provided withprotective sheathing of resilient fibrous or metallic material, or acombination of one or more of these.

In those instances where conduits have been employed to enclose thecables, the expense involved has been exceedingly great, due to both thecost of the conduits and the Wages of skilled labor required to installthem. They have also been attended by certain disadvantages, in that, ifa conduit is laid through a crowded section, it is necessary to suspendactivity while the roadway is torn up and repaved.

The cables installed Without conduits, have given rise to certaindifficulties that have never heretofore been surmounted. The generallyaccepted practice has been to encase the conductor and insulationpreviously applied, with a continuous sheath of lead or other metal andfurther enclose the whole with one or two layers of spirally Wrappedband steel or other metal or metals, a sheathing of fabric Wound underand over the metallic wrapping for cushioning purposes.

This invention consists in general of the provision of an electric cableintended for subterranean use but adaptable as well for submarine andaerial installation, having a protective covering that will effectivelyresist the deleterious eiects of weathering and protect the insulatedelectrical conductor from mechanical injury.

It further consists in the provision of an electric cable dispensingwith the customary metallic protective sheathing and windings withoutlosing its ability to withstand natural or Vmechanical in- Jury.

An object of this invention is to provide an electric cable having anouter protective covering that will effectively resist weathering.

Another object of this invention is to provide an electric cable havingprotective sheathing that will effectively 'resist mechanical injury.

Yet another object of this invention is to provide an electric cablehaving pliant and flexible outer protective coverings.

Still another object of this invention is to provide an electric cablehaving outer protective covering that may be easily repaired.

A further object of this invention is to provide an electric cable withprotective covering which has no impedance effect on the circuit inwhich the conductor is located.

A still further object of this invention is to provide an electric cabledispensing with the customary metallic sheathing without seriouslyimpairing its ability to withstand natural and mechanical injuries.

Yet a further object of this invention is to provide an electric cabledispensing with the customary metallicsheathing having an outer coveringthat Will effectively resist the deleterious effects of weathering.

With these and other objects in view which may be incident to myimprovements, the invention consists inthe parts and combinations to behereinafter set forth and claimed, with the understanding that theseveral necessary elements comprising my invention, may be varied inconstruction, proportions and arrangement, without departing from thespirit and scope of the appended claims.

In order to make my invention more clearly understood, I have shown inthe accompanying drawings means for carrying the same into practicaleffect, without limiting the improvements in their useful applicationsto the particular constructions, which for the purpose of explanation,have been made the subject of illustration.

In the drawingsforming a part of this specication:

In Figure 1 is shown a side elevational view of the improved cableforming the subject matter of this invention;

In Fig. 2 is shown a top plan view taken on line 2-2 of Fig. 1;

In Fig. 3 is shown a side elevational View of a modification of Fig. 1;

In Fig. 4 is shown a side elevationalview of a modication of Fig. 1;

In Fig. 5 is shown a side elevational View of a modiiication of Fig. l;

In Fig. 6 is shown a top plan view taken on line 6 6 of Fig. 5;

In Fig. 7 is shown a side elevational view of a modification of Fig. 5;

Referring by numerals to the drawings wherein the same and similarelements are designated by like symbols of reference throughout, andmore particularly to Fig. l, 1 is representative of an electricconductor composed of any suitable highly conductive material, generallycopper. The conductor is encased in insulation 2 composed of rubber,paper, cambric or other commonly used insulating material. Over theinsulation a spirally wrapped insulating tape, or impregnated braid 3 isapplied, thoughthis is not an essential element of the invention.

Around the insulation or tape or braid there is wound a layer of jute orother cushioning or protecting material 4, thoroughly waterproofed bysaturation with an asphaltum compound, paraffin or any other desirablesuitable substance or compound.

At this point there is applied two layers of nonmetallic protectivestrips 5 and 6, adapted to further protect the cable. These strips arehelically wound, the outer strip being adapted to be wound in staggeredrelation to the inner strip so as to cover the spaced adjacent helicaledges of the inner strip.

Another form of winding is shown in Figure 3 wherein the non-metallicstrips 5 and 6 are helically wound in crisscross relation. For certainpurposes this type of winding affords greater rigidity to preventlooping of the cable as it precludes both lateral and rotational bightswhile the helical winding offers safeguard only against lateral bights.Over this winding is adapted to be wound a layer of jute or other ber 'Ithoroughly saturated with asphaltum compound, paran or any othersuitable substance or compound. This covering is designed to lendpliancy and exibility to the cable thus excluding fractures or crackingin the outer surface and preventing the inner protective covering frombecoming exposed.

As shown in Fig. 4 the covering heretofore specified may be applied overa plurality of conductors 1 and l', in the same manner as over a singleconductor.-

If it be so desired an additional sheathing may be added of an integralmetallic nature to the protective covering as shown in Fig. 5, wherein ametallic sheath 8 is imposed over the fabric Winding 3, having woundthereover the jute ycovering 4. The protective windings 5 and 6 may behelically wound in either staggered relation or crisscross relation asshown in Fig. 7.

The use of this type of protective coverings instead of steel bands isadapted to reduce the weight of the cable and remove the likelihood ofcurrent losses, without materially affecting the cables abilty towithstand mechancal or natural injury. Over the integral metallic sheath8 is wound the treated jute or other fiber 4 in a man- `ner heretoforedescribed. This material from which the layers 5 and 6 are formed may beof a fabric or of a fibrous nature and possessing a sufllcient degree ofresistance to mechanical stresses to afford ample protection to theenclosed insulated electric conductor, and treated with any suitablecomposition to render vit entirely waterproof. These may be eitherhelically wound as previously explained in staggered relation, or thesecond tape so applied as to cover the openings in adjacent convolutionsof the first tape in crisscross relation. The completed cable may betreated with powdered chalk, soap stone or any similar substance toprevent adhesion.

It must be borne in mind that the strips 5 and 6 must be strong andstiff enough to protect the conductor from injury, such as a glancingblow of a pick or other instrument used in connection with placing thecable in position.' I do not Wish to be specifically limited to aparticular type of material to accomplish this purpose, but there arecertain materials which I have used and which I find to have admirableproperties for the purpose which I have in mind.

The layers 5 and 6 may be formed of a heavy treated duck, which istreated with varnish and the varnish then baked in. This gives a pliableconstruction, non-inductive and non-magnetic, yet of suflicient hardnessand toughness to serve the purpose of a protecting layer serving thefunctions herein speced.

Another type of material which has proven useful for the purposedesignated is that type of composition which may be designated by thebroad generic term of fabricoid material. By this I mean such materialsas are used for automobile tops. This material can be made of suflcientstiffness to serve the purpose and is nonmagnetic and non-inductive inits action.

Other materials which have proved advantageous are vulcanized ber andcertain of the phenolic condensation products, such as bakeli It isnecessary that these phenolic condensation products not have the maximumdegree of stiffness, since they may be so stiff as to be brittle, andthis is of course a property which must be avoided in selection of thematerial for the purpose of these protective Wrappings 5 and 6. 105

Another type of material which may be used is that material known on themarket as Micarta. This is a composite material formed of layers ofheavy duck orv canvas impregnated with a phenolic condensation productsuch as bakelite. As above pointed out, the impregnating phenoliccondensation product used must be in such condition as to avoid thedegree of hardness which would impart to it an undesirable brittleness.Also certain paper and fibrous Wrappings specially treated to give themtoughness and make them waterproof may be employed.

I accomplish by this invention an improved electric subterranean cable,adaptable to submarine and aerial use as well, provided with a pliantand flexible outer waterproof covering made to afford ample protectionagainst mechanical injury as well as the deleterious effect ofweathering.

There is further accomplished an electric cable dispensing with thecustomary metallic coverings having a pliant and flexible outerwaterproof covering precluding magnetic induction, or transformer loops,and serving the double purpose of a safeguard against mechanical injuryand the deleterious effects of weathering.

While I have shown and described the preferred embodiment of myinvention, I Wish it to be understood that I do not confine myself tothe precise details of construction herein set forth, by way ofillustration, as it is apparent that many changes and variations may bemade therein, by those skilled in the art, without departing from thespirit of the invention, or exceeding the scope of the appended claims.

I claim:

l. An electric cable comprising a conductor, a resilient insulationaround the conductor, an impregnated fabric sheath around the resilientinsulation, an impregnated fibrous wrapping 145 around the fabricsheath, a plurality of strips of stiff bendable non-magnetic,non-conducting material helically wound around the impregnated erouswrapping, and an impregnated fibrous Wrapping around the helically4wound strips.

2. An electric cable comprising a plurality of conductors, a resilientinsulation' around each conductor, an impregnated fabric sheath aroundeach resilient insulation, an impregnated fibrous wrapping around thefabric sheaths, a plurality of strips of stiff bendable non-magnetic,nonconducting material helically wound around the' impregnated brouswrapping', and an impregnated brous wrapping around the helically woundstrips.

3. An electric cable comprising a conductor, a

resilient insulation around the conductor, 'an im-y pregnated fabricsheath around the resilient insulation, a metallic sheath around the'fabric sheath, an impregnated fibrous wrapping around the metallicsheath, a plurality of strips of stiff bendable non-metallic,non-conducting material helically wound around the impregnated brouswrapping, and an impregnated brous wrapping around the helically woundstrips.y

cam. P. BRODHUN.

